jamal

So, to get this straight, you're saying that engine braking can pull a rod apart in tension? Specifically in an EJ? When has this ever happened? Uh, no, actually, most metals have nearly the same yield strength in both tension and compression. I can all but guarantee that a rod through the block in a Subaru is caused by one of two things: 1) oil starvation to the rod bearings due to sustained high revs. 2) detonation due to overheating after sustained high load. These are not things that happen on a stock car in good working order, and sometimes on cars are modified for power and tracked continuously. Rods are not just going to snap because you have 250k miles and are driving in the mountains.

it isn't either of the cars listed in your profile?

If you can get the backing plate on, you're partway there. The backing plate is pressed onto the knuckle, and the caliper bracket and parking brake assembly attach to it. Then you have to figure out how to get the rotor to work, and how to get it in the right place. Did they not make any EA82 cars with rear discs? Is it possible to do an EJ hub conversion? Those would be my first two options.

When the Impreza came out, the TCU got fuel cut logic, but the 1st gen legacy and SVX kept the "upshift" logic. Even with the selector in 1 it will upshift. In 2-manual mode (which only works in 2 and 3) it will still upshift to 3rd. When you slow back down it will downshift, sometimes rather abruptly. Can you tell that I read endwrench articles for fun?

SVX and 1st gen Legacy automatics upshift.

I thought it was the Italian tune-up.

if the motor is cold, yes. Otherwise no.

Actually combustion chamber pressure has a more direct correlation with torque and the load on the motor. So pressures might be the highest at peak torque, and they decrease above that. Horsepower is a function of torque and rpm, so even though a motor isn't producing the max torque above 4400 or whatever rpm, it's spinning faster and making more horsepower. if you're lugging the motor detonation will occur which creates very high combustion chamber pressures.

It will if the bolt is stuck to the metal insert of the bushing, which seems pretty likely.

a dealership is the only place. Subiegal is the internet parts person for a dealership in WA. PM her and she will look up the bolts for you. My point is that it will be very difficult to remove the bolt without ruining the bushing in the lateral link. Instead of trying to take the bolt out, possibly destroying various bushings, then maybe having to destroy other bushings to get the link out, then having to find new bushings and get them pressed in, it might be better to buy a set of used links and all new hardware.

a used set of lateral links isn't too hard to find on nasioc. WRX wagon, 93-01 Impreza, and 92-99 Legacy links will all work. I paid $40 for a full set. Here is what it took to remove an old one: You should buy all new hardware while you're at it. Subiegal can get you everything at a good price.

did you read the whole thread?

You do not have anything to worry about. I'll still suggest some Hawk HPS pads. They're one of the few street performance pads for your car. I really liked them and have also heard good things (primarily from Subiegal, a real race car driver) about EBC red and yellowstuff. While the motor is turning fast, it's circulating coolant and oil at a rate that will keep things cool and lubricated under full throttle, and the heat and all of the forces in the motor are much less while engine braking. There is no way in hell you are going to spin a bearing because of the tensile forces in the rods. Metals are great materials because they can withstand forces in any direction. Additionally tension in the rod is going to create a much lower force on the bearing than the other side sees on a power stroke. The whole reason for a redline is that you'll be pretty much fine operating the motor anywhere below that. The big limitations to Subaru motors are cooling, the valve train, and lubrication to the main bearings. Cooling obviously isn't a problem for you, valves don't float until somewhere over redline, and the crank needs to be spinning at over 8krpm before the oil pressure/flow isn't high enough to lubricate the rod bearings.

Cool. My understanding was that when the fluid overheats it loses some ability to resist shear (i.e. lock the diff). Obviously this isn't the case here, but whether it is due to the fluid or the "hump effect" I mentioned earlier I can't say. Well, it is the same person... Here's an example of a vc not working, though: http://forums.nasioc.com/forums/showthread.php?t=325909

any other automatic impreza driveshaft should work as far as I know.

yeah, the older 4eat cars are front biased. Unless the fronts slip or the tcu has reason to send more power rearward with a clutch pack, you basically have a fwd car. I would still prefer to have a 5-speed with a stronger center diff (well, after the dccd sti), because it operates at 50:50 during normal driving. The new automatics with VTD are much better, have a rear bias, and can transfer much more power to the front or rear. Instead of a clutch pack that just sends some power to the rear or a VC, they have a planetary gearset in a system similar to the STi. The sti uses clutches in the center differential instead of a viscous coupling, and a computer that takes inputs from a lot of sensors to determine how much the center diff should lock. It also provides even more rear bias, and has way better front and rear differentials. I guess I'll try to dig up a newer service manual to learn more about vtd one of these days.

Well, it would be easy enough to plot some points to get an idea of the torque/rpm curve for the vc, especially if you had a really big torque wrench. MRT sticks them on a lathe, attaches a torque wrench to the other end, and turns it at 100 rpm to measure the resistance. Finding the upper limit might be difficult, though. And you're welcome, but if I didn't want to do this I wouldn't post.

Skip, the error in your illustration is where the viscous coupling is hanging off the back of the center differential. The VC is actually inside the center differential, between the front and rear driveshafts. Picture time. From the motor, power goes through the clutch to the the main shaft, which has all the drive gears. The drive gears are meshed with the driven gears, which are on the driven shaft, which is hollow. Here is the transmission: The main shaft, which is connected to the clutch, is blue. The driven shaft is yellow and the front diff is green. Here is the driven shaft: The part highlighted in red is the drive pinion. It is inside the driven shaft. Here is an exploded view: Once again the red part is the drive pinion. The little part highlighted in yellow is where the driven shaft connects to the center differential. All those other things are the driven gears, dogs, collars, and syncros, etc. Here is the center differential: The red is where the drive pinion connect to the differential. The yellow is where the driven shaft connects to the center differential. The viscous coupling is purple. As you can see, it's part of the center diff and is connected to both the front and rear output. The red part labeled "10" connects to the rear transfer drive gear. Here is the transfer case: Yellow, once again, is where the driven shaft connects. Blue are the transfer gears to send power to the rear. Red is where the transfer driven shaft connects to the center differential (item 10 in the previous picture). How does this all work? Power goes from the clutch to the main shaft, through the selected gear to the driven shaft which turns the center diff. From there it is split to the front diff and through the transfer gear to the rear diff. When there is a speed difference between the front and rear, the viscous coupling heats up and tries to speed up the slower moving end. Now, the viscous coupling is not supposed to be able to transfer all of the power to one end. The stock unit is rated at 4 kg-m/100rpm. What that means is that for a 100 rpm speed difference in the coupling, it will provide 4 kg-m, or about 28 lb-ft, of resistance. However, this relationship is not linear (one of the downsides to a vc), and there is a limit to how much power can actually be transferred. 200 rpm difference does not mean 56 lb-ft is transferred. How much the vc can actually lock up, I'm not sure. For all I know it's proprietary information that Subaru doesn't release. What I can say is that it is much less than the full power of a car. Some guy on nasioc jacked up the rear of a WRX, put a 2x4 on the ground in front of the front wheels, and put the car in gear. The car was unable to pull itself over the wood by the front wheels and the rears just sat there spinning in the air, even after revving it to over 4k rpm. Subaru does, however, make stronger center viscous couplings, in 10, 12, and 20 kg-m/100rpm varieties. Everything I have heard about the 20 is that you should not use it driving around on the street, and that it will bind up and cause hopping etc as if the 4wd was engaged in a truck. Seems to be good in rally cars, though. Now, in Dan's case, the VC has somehow bound up and is fused together. Can he rely on this to get him around? I'd say no, and I guess that answers the original question.

you could possibly take the airbags and harness out of the 06 seats and put them in the 03 seats. A guy on nasioc took the airbags out of his sti seats to run with his race buckets, which I thought was questionable but they are in the same place. Zippers on the back should let you peel the upholstery off enough to remove the bags.

no baffles, you can just pull the pan off and replace it or bend it back. Some 4eats used a gasket and some just use sealant. I'd recommend just getting some sealant. Expect to get atf in your hair, though. I took pictures and stuff when I replaced the gasket, they're here: http://bbs.legacycentral.org/viewtopic.php?t=28316

That is not a Subaru center diff/viscous coupling. The VC is not off the back, only providing rear assist when the fronts spin. If that were the case, it would have to lock it up before the car could even move, because initally the rear output would just spin. The subaru unit is one combined part that will allow either the front or rear to spin faster to "lock up" the VC.

No, the link nipper posted was correct. But what people seem to be missing is the part that says "a regular center differential which distributes torque to the front and rear." The viscous coupling acts to limit slip. So what you have is a VLSD transferring power front and rear. The driven shaft (what the output/driven gears are connected to) does not directly drive the front differential, as nipper posted. It drives the center differential. The drive pinion shaft, as it's called, which goes to the front ring gear, is inside the driven shaft, and is connected to the front output of the center diff. The rear output goes through a transfer gear and then to the rear wheels.

Oh, okay sorry, I edited it to say "some" Anyway, more than one person has ruined a center diff/duty c with the switch.

Like I said earlier, your 4eat will be fine in FWD. The 4eat is FWD based and uses a clutch to transfer power rearward. Putting a fuse in a holder under the hood disables power transfer to the rear, but will cause damage to the duty solenoid C after extended periods of time (see some the people who made switches to force it on or off). The manuals don't just use a viscous coupling off the rear to transfer power, they actually have a center differential. Found an interesting piece of info about the viscous coupling in an old nasioc thread: post 54 here How much power can transfer to the front and for how long is not something I'd be inclined to experiment with. I guess we'll find out when Dave833 gets stranded somewhere.

looking. There are some great tech docs about how dccd works floating around (this pretty much covers it). MRT has a few pictures of the standard center diff/VC. http://www.mrtrally.com.au/performance/viscous_coupling.htm Their drawing is just a generic viscous coupling and not was is really in a subaru